======================================
| [  206.313868][  T819] ==================================================================
| [ 206.314105][ T819] BUG: KASAN: null-ptr-deref in nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
| [  206.314316][  T819] Read of size 4 at addr 0000000000000068 by task ip/819
| [  206.314489][  T819]
[  206.314569][  T819] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  206.314572][  T819] Call Trace:
[  206.314574][  T819]  <TASK>
[ 206.314576][ T819] dump_stack_lvl (lib/dump_stack.c:123) 
[ 206.314584][ T819] kasan_report (mm/kasan/report.c:636) 
[ 206.314590][ T819] ? nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 206.314596][ T819] kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189) 
[ 206.314600][ T819] nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 206.314606][ T819] ? __pfx_nexthop_create_group (net/ipv4/nexthop.c:2686) 
[ 206.314609][ T819] ? __nla_validate_parse (lib/nlattr.c:638) 
[ 206.314617][ T819] rtm_new_nexthop (net/ipv4/nexthop.c:2937 net/ipv4/nexthop.c:3254) 
[ 206.314621][ T819] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 206.314627][ T819] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 206.314632][ T819] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 206.314644][ T819] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6952) 
[ 206.314652][ T819] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 206.314656][ T819] rtnetlink_rcv_msg (net/core/rtnetlink.c:6954) 
[ 206.314661][ T819] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 206.314664][ T819] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 206.314667][ T819] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 206.314671][ T819] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 206.314676][ T819] netlink_rcv_skb (net/netlink/af_netlink.c:2534) 
[ 206.314681][ T819] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 206.314685][ T819] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2511) 
[ 206.314693][ T819] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340) 
[ 206.314696][ T819] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/net/netns/generic.h:48 net/netlink/af_netlink.c:333) 
[ 206.314699][ T819] netlink_unicast (net/netlink/af_netlink.c:1313 net/netlink/af_netlink.c:1339) 
[ 206.314703][ T819] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1324) 
[ 206.314706][ T819] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 206.314711][ T819] netlink_sendmsg (net/netlink/af_netlink.c:1883) 
[ 206.314715][ T819] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1802) 
[ 206.314722][ T819] ____sys_sendmsg (net/socket.c:709 net/socket.c:724 net/socket.c:2563) 
[ 206.314730][ T819] ? __pfx_____sys_sendmsg (net/socket.c:2509) 
[ 206.314733][ T819] ? __pfx_copy_msghdr_from_user (net/socket.c:2489) 
[ 206.314740][ T819] ___sys_sendmsg (net/socket.c:2619) 
[ 206.314743][ T819] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 206.314746][ T819] ? __pfx____sys_sendmsg (net/socket.c:2606) 
[ 206.314751][ T819] ? hlock_class (kernel/locking/lockdep.c:225) 
[ 206.314756][ T819] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[ 206.314761][ T819] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[ 206.314765][ T819] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 206.314769][ T819] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 206.314773][ T819] __sys_sendmsg (net/socket.c:2649) 
[ 206.314776][ T819] ? __pfx___sys_sendmsg (net/socket.c:2634) 
[ 206.314781][ T819] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:742 arch/x86/mm/fault.c:1339) 
[ 206.314786][ T819] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 206.314791][ T819] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[  206.314796][  T819] RIP: 0033:0x7f789efba9a7
[ 206.314801][ T819] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
All code
========
   0:	0a 00                	or     (%rax),%al
   2:	f7 d8                	neg    %eax
   4:	64 89 02             	mov    %eax,%fs:(%rdx)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b9                	jmp    0xffffffffffffffc9
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 2e 00 00 00       	mov    $0x2e,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  3b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  11:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
[  206.314803][  T819] RSP: 002b:00007ffecedad518 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  206.314808][  T819] RAX: ffffffffffffffda RBX: 00007ffecedae080 RCX: 00007f789efba9a7
[  206.314810][  T819] RDX: 0000000000000000 RSI: 00007ffecedad580 RDI: 0000000000000005
[  206.314812][  T819] RBP: 00007ffecedada40 R08: 0000000000000004 R09: 00007f789ef38980
[  206.314814][  T819] R10: 00007f789ee73708 R11: 0000000000000246 R12: 00007ffecedae997
[  206.314815][  T819] R13: 0000000067da3a4f R14: 0000000000498600 R15: 0000000036b51910
| [  206.323040][  T819] Disabling lock debugging due to kernel taint
| [  206.323446][  T819] Oops: general protection fault, probably for non-canonical address 0xdffffc000000000d: 0000 [#1] PREEMPT SMP KASAN NOPTI
| [  206.323774][  T819] KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
| [  206.324197][  T819] Tainted: [B]=BAD_PAGE
[  206.324295][  T819] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 206.324462][ T819] RIP: 0010:nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 206.324634][ T819] Code: 5c 09 00 00 45 3b 7e 60 72 c0 76 06 49 83 c6 08 eb bc 4d 8d 7e 68 be 04 00 00 00 4c 89 ff e8 84 19 2f fe 4c 89 f8 48 c1 e8 03 <42> 0f b6 14 20 4c 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85
All code
========
   0:	5c                   	pop    %rsp
   1:	09 00                	or     %eax,(%rax)
   3:	00 45 3b             	add    %al,0x3b(%rbp)
   6:	7e 60                	jle    0x68
   8:	72 c0                	jb     0xffffffffffffffca
   a:	76 06                	jbe    0x12
   c:	49 83 c6 08          	add    $0x8,%r14
  10:	eb bc                	jmp    0xffffffffffffffce
  12:	4d 8d 7e 68          	lea    0x68(%r14),%r15
  16:	be 04 00 00 00       	mov    $0x4,%esi
  1b:	4c 89 ff             	mov    %r15,%rdi
  1e:	e8 84 19 2f fe       	call   0xfffffffffe2f19a7
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
  2a:*	42 0f b6 14 20       	movzbl (%rax,%r12,1),%edx		<-- trapping instruction
  2f:	4c 89 f8             	mov    %r15,%rax
  32:	83 e0 07             	and    $0x7,%eax
  35:	83 c0 03             	add    $0x3,%eax
  38:	38 d0                	cmp    %dl,%al
  3a:	7c 08                	jl     0x44
  3c:	84 d2                	test   %dl,%dl
  3e:	0f                   	.byte 0xf
  3f:	85                   	.byte 0x85

Code starting with the faulting instruction
===========================================
   0:	42 0f b6 14 20       	movzbl (%rax,%r12,1),%edx
   5:	4c 89 f8             	mov    %r15,%rax
   8:	83 e0 07             	and    $0x7,%eax
   b:	83 c0 03             	add    $0x3,%eax
   e:	38 d0                	cmp    %dl,%al
  10:	7c 08                	jl     0x1a
  12:	84 d2                	test   %dl,%dl
  14:	0f                   	.byte 0xf
  15:	85                   	.byte 0x85
[  206.325088][  T819] RSP: 0018:ffffc900019673c8 EFLAGS: 00010202
[  206.325259][  T819] RAX: 000000000000000d RBX: ffff88800272cae8 RCX: ffffffffad453d8a
[  206.325454][  T819] RDX: fffffbfff64e2491 RSI: 0000000000000008 RDI: ffffffffb2712480
[  206.325646][  T819] RBP: 0000000000000000 R08: 0000000000000001 R09: fffffbfff64e2490
[  206.325838][  T819] R10: ffffffffb2712487 R11: 205d393138542020 R12: dffffc0000000000
[  206.326034][  T819] R13: ffff888008d8f000 R14: 0000000000000000 R15: 0000000000000068
[  206.326232][  T819] FS:  00007f789edae800(0000) GS:ffff888036180000(0000) knlGS:0000000000000000
[  206.326456][  T819] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  206.326620][  T819] CR2: 00007f789f00a423 CR3: 000000000f86a003 CR4: 0000000000772ef0
[  206.326813][  T819] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  206.327011][  T819] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  206.327208][  T819] PKRU: 55555554
[  206.327318][  T819] Call Trace:
[  206.327420][  T819]  <TASK>
[ 206.327489][ T819] ? die_addr (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:460) 
[ 206.327596][ T819] ? exc_general_protection (arch/x86/kernel/traps.c:751 arch/x86/kernel/traps.c:693) 
[ 206.327732][ T819] ? asm_exc_general_protection (./arch/x86/include/asm/idtentry.h:617) 
[ 206.327866][ T819] ? add_taint (./arch/x86/include/asm/bitops.h:60 ./include/asm-generic/bitops/instrumented-atomic.h:29 kernel/panic.c:605) 
[ 206.327967][ T819] ? nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 206.328097][ T819] ? nexthop_create_group (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/linux/refcount.h:136 ./include/linux/refcount.h:142 ./include/linux/refcount.h:218 ./include/linux/refcount.h:236 ./include/net/nexthop.h:264 net/ipv4/nexthop.c:2721) 
[ 206.328241][ T819] ? __pfx_nexthop_create_group (net/ipv4/nexthop.c:2686) 
[ 206.328370][ T819] ? __nla_validate_parse (lib/nlattr.c:638) 
[ 206.328501][ T819] rtm_new_nexthop (net/ipv4/nexthop.c:2937 net/ipv4/nexthop.c:3254) 
[ 206.328636][ T819] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 206.328772][ T819] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 206.328873][ T819] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 206.329009][ T819] ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/core/rtnetlink.c:6952) 
[ 206.329143][ T819] ? __pfx_rtm_new_nexthop (net/ipv4/nexthop.c:3225) 
[ 206.329283][ T819] rtnetlink_rcv_msg (net/core/rtnetlink.c:6954) 
[ 206.329477][ T819] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 206.329685][ T819] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 206.329897][ T819] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 206.330056][ T819] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 206.330266][ T819] netlink_rcv_skb (net/netlink/af_netlink.c:2534) 
[ 206.330474][ T819] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6857) 
[ 206.330683][ T819] ? __pfx_netlink_rcv_skb (net/netlink/af_netlink.c:2511) 
[ 206.330895][ T819] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 net/netlink/af_netlink.c:340) 
[ 206.331098][ T819] ? netlink_deliver_tap (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/net/netns/generic.h:48 net/netlink/af_netlink.c:333) 
[ 206.331315][ T819] netlink_unicast (net/netlink/af_netlink.c:1313 net/netlink/af_netlink.c:1339) 
[ 206.331489][ T819] ? __pfx_netlink_unicast (net/netlink/af_netlink.c:1324) 
[ 206.331646][ T819] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 206.331779][ T819] netlink_sendmsg (net/netlink/af_netlink.c:1883) 
[ 206.331909][ T819] ? __pfx_netlink_sendmsg (net/netlink/af_netlink.c:1802) 
[ 206.332042][ T819] ____sys_sendmsg (net/socket.c:709 net/socket.c:724 net/socket.c:2563) 
[ 206.332175][ T819] ? __pfx_____sys_sendmsg (net/socket.c:2509) 
[ 206.332309][ T819] ? __pfx_copy_msghdr_from_user (net/socket.c:2489) 
[ 206.332472][ T819] ___sys_sendmsg (net/socket.c:2619) 
[ 206.332599][ T819] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 206.332729][ T819] ? __pfx____sys_sendmsg (net/socket.c:2606) 
[ 206.332859][ T819] ? hlock_class (kernel/locking/lockdep.c:225) 
[ 206.332992][ T819] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[ 206.333124][ T819] ? do_user_addr_fault (./include/linux/rcupdate.h:337 ./include/linux/rcupdate.h:849 ./include/linux/mm.h:740 arch/x86/mm/fault.c:1339) 
[ 206.333261][ T819] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 206.333394][ T819] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 206.333522][ T819] __sys_sendmsg (net/socket.c:2649) 
[ 206.333653][ T819] ? __pfx___sys_sendmsg (net/socket.c:2634) 
[ 206.333783][ T819] ? do_user_addr_fault (./include/linux/rcupdate.h:882 ./include/linux/mm.h:742 arch/x86/mm/fault.c:1339) 
[ 206.333912][ T819] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) 
[ 206.334043][ T819] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) 
[  206.334206][  T819] RIP: 0033:0x7f789efba9a7
[ 206.334349][ T819] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
All code
========
   0:	0a 00                	or     (%rax),%al
   2:	f7 d8                	neg    %eax
   4:	64 89 02             	mov    %eax,%fs:(%rdx)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b9                	jmp    0xffffffffffffffc9
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 2e 00 00 00       	mov    $0x2e,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  3b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  11:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
[  206.334805][  T819] RSP: 002b:00007ffecedad518 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  206.335000][  T819] RAX: ffffffffffffffda RBX: 00007ffecedae080 RCX: 00007f789efba9a7
[  206.335200][  T819] RDX: 0000000000000000 RSI: 00007ffecedad580 RDI: 0000000000000005
[  206.335401][  T819] RBP: 00007ffecedada40 R08: 0000000000000004 R09: 00007f789ef38980
[  206.335595][  T819] R10: 00007f789ee73708 R11: 0000000000000246 R12: 00007ffecedae997


Finger prints:
nexthop_create_group:rtm_new_nexthop:rtnetlink_rcv_msg:netlink_rcv_skb:netlink_unicast
kasan_report:kasan_check_range:nexthop_create_group:rtm_new_nexthop:rtnetlink_rcv_msg